@evan yay! Hazelnuts are great, perfect use of shade/understory. I grew a bush at a previous place in Oakland.
Fun/sad-ish personal trivia: hazelnuts were my father's last obsession (he kind of moved from hobby to hobby) before really going downhill. I heard many impromptu and unwanted lectures on their processing and use though he was a newbie and wouldn't acknowledge that I grew them first and consumed them all the time or that they are available in stores...